Link for IITJEE 2012 Solution from Coaching institutes website

Resonance

http://www.resonance.ac.in/reso/news/iitjee-answerkey-solutions.aspx

FIITJEE

http://www.fiitjee.com/fiitjeejava/jsp/iitjeesolution2012/coming.jsp

Vidyamandir Classes

 https://sites.google.com/a/vidyamandir.com/iitjee2012/

Bansal

http://bansaliitjee.com/iitjee_2012_Rank.aspx


Aakash IITJEE

http://www.aakash.ac.in/iit-jee-answers-key-with-solutions

Naryana IIT Academy

http://www.narayanagroup.com/iitjee2012key-sol/iitjeepaper-1-code-1-key-sol-final.pdf

Vibrant Academy

http://www.vibrantacademy.com/vibrant/IIT_2012.aspx